| 829 or GU-29 audio amplifier schematics? - Click HERE for Original Thread |
| AcidEye |
I'm looking for audio amplifier schematics using 829 or GU-29 tubes. After searching this forum, no schematics of my "taste" could be found for these tubes... The following interesting schematic was found for the little brother of the 829, the 832:
http://www.audiohobbyist.com/projects/832.htm
Does anyone have a comparable schematic for an amplifier with the 829 or GU-29 tube (more output than 832)? SE schematics are also welcome!
Kr,
Martin |
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| AcidEye |
Thanx!
These schematics are new for me, maybe I should start searching with Russian characters :-)
Today, I've located the sockets for these tubes at an affordable price, it will take some time before I've located all parts for a complete amp. |
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| rtirion |
You might want to take a look at
www.ultranalog.com
coldwar.
You will find a lot of usefull info there.
I build this fine sounding amp some years ago.
Regards |
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| AcidEye |
For those who are interested in amplifiers with these kind of tubes, I've found a nice project with a tube comparable to the 829 on Jogis page:
http://www.jogis-roehrenbude.de/Les...E29-SE/3E29.htm
For this SE amplifier, the JAN 3E29 tube is used (which is mentioned to be similar to the 829). |
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| adalin |
Saw this thread on friday and thought for myself, this I must try
I built a prototype today and I find it quite interresting I must say, the first thing I notised was that the amp is completely noiseless.
When I started the first channel to test it I thought it didnt work, there was no hum or fiss in my speaker. Then I turned the sinusgenerator on and sure, there was sound :)
I havent meassured dist and outputpower yet but there is potensial in this tube, I will build one in a real chassi, thats for sure :)
Got a bad pic from the prototype, I got no real camera so no closeups :(
tubeamp |
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| AcidEye |
Hi Adalin,
The results from your prototype sound very promising!
Did you use the 829/GU-29 or the 832/GU-32 tube for this setup? What schematic and operating voltage are you using?
Please keep us informed on your project and findings, I like the concept of using unusual tubes for audio applications :-)
Kind regards,
Martin |
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| adalin |
I have a small stock of 832-A philips and some qqe06/40 I can try both in the amp just have to change the bias a little, I got no 829 Im afraid.
distortion, hmmm worse than I expected. with the 832 @ 7W outputpower I have 2,5% and the 1% mark is at 4W measured with my ferrograph
but if one compare it with disortion
its allmost spot on.
Its not a high power unit :) one can probably squeese out a few extra watts with qqe 04/60 I guess but i have not tried yet |
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| AcidEye |
Adalin,
From what I have found on 832 audio amplifiers on the Internet, the output power in PP does not exceed 10W (7W is OK). Do you apply feedback with your setup? If yes, what resistor value are you using in the feedback link?
Both GU-29 and GU-32 tubes are frequently found on Ebay for a reasonable price (between $3 and $5 each). For those who happen to have a pile of output transformers on the shelve, a nice (and cheap!) way to get some experience with the less common (but still interesting) tubes available :-)
Kind regards,
Martin |
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| AcidEye |
| I have found a nice 829B schematic, using the 6N9P for preamp and phase shift: |
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| soundbrigade |
I had planned to glue a 829SE together but I sort of came to a conclusion that the transformers intended for the job were too small so I am going to use a 807 instead.
The original idea was something like this:
http://www.pastisch.se/faktiskt/6sj7_829b.jpg
I have a pushpull design design similar to some 832PP-amps.
http://www.pastisch.se/faktiskt/k_6N9P_829B.pdf
The 6N9P is confusing. I can find a (Russian tube) 6N9C = 6SL7 in my lists and a 6N6P = 12BH7A but not a 6N9P... |
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| soundbrigade |
Ooops the 829PP was already posted.
| quote: | | Both GU-29 and GU-32 tubes are frequently found on Ebay for a reasonable price (between $3 and $5 each). For those who happen to have a pile of output transformers on the shelve, a nice (and cheap!) way to get some experience with the less common (but still interesting) tubes available :-) |
I find no information what so ever about the Pout from 829 and 832 in PP and SE respectively.
A 832PP is scheduled - got a pair of nice (blue) X-formers from Edcoreusa: 10W, 8Kohm Raa, 8ohm O/P. |
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| AcidEye |
The 6SL7 is known in China as the 6N9P:
US 6SL7
Chinese 6N9P
Russian 6N9S
Since the last schematic I have posted is from China (there are some Chinese characters visible in this schematic), the 6N9P is used. I have ordered some 6N9S tubes for the preamp and phase shift section of this amplifier.
I plan to use PP transformers from a local company (www.klare.nl) for this setup, they sell 30W PP transformers (8K primary) at a reasonable price.
The Chinese schematic promises 20W (@ 10% distortion without NFB...) using the 829 as power tube. Most 832 setups report about 7W in PP. |
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| soundbrigade |
Thanks for the answers!
I belong to a Swedish HiFi-forum where there has been a discussion on so called UFO-tubes (UFO-tube spotting ) The duo 829/832 are tubes that look queer and pose a challange to be put into amplifying audio signals. And the idea of using ONE tube for a PP-amp is thrilling.
However I follow up with yet another question. How to you (who use these tubes) arrange for a connection to the "anode horns"? |
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| AcidEye |
I haven't found a ceramic anode connector dedicated for this tube. Looking at the audio projects on Internet with these tubes, several improvised solutions can be found:
Wire-wrapping: looks like a very reliable connection, often found in mil-spec equipment. Only solid copper wire can be used for this type of connection.
Soldring: with a risk of damaging the tube, solder the wire directly on the anode pins. I'm not sure if the solder connection is reliable when heated by the vacuum tube.
PC connector: some brave people have trashed a powerconnector of a PC powersupply and removed the pins of one of the plugs. These connectorpins seem to have the right size for a good clamp on the anode pin. Advantage with this setup is that you can use flexible silicone wire soldered to the connector pin, without risk of damaging the tube. |
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| soundbrigade |
| Just remembered, I bought new connectors för my Priboi in Russia - guess the pin size for 6R3S is the same as for 829/832 - else I have seen nothing. |
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| adalin |
I just finnished a new chassie for my amp and hopefully all the pieces will fit in it :)
I use the PC connector style for my anodepins, it works pretty good |
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| soundbrigade |
About odd looking (HF-tubes), I've got a schematic of a SE-amp using a (Russian) GU72. (Could it be an 872???)
Have you seen that one? |
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| AcidEye |
| I've googled for the GU-72, looks like a very powerfull HF tube. I haven't seen audio schematic for this tube, if you have some please share them with us :-) |
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| soundbrigade |
The only amp I have fond (so far) is this one SEGU72
But I am still oogling and googling.
The 6C2C are equivalent to 6J5GT. |
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| alexg |
| quote: | Originally posted by adalin
I just finnished a new chassie for my amp and hopefully all the pieces will fit in it :)
I use the PC connector style for my anodepins, it works pretty good |
I have a bunch of 832 and would love if you can give me a schematic of the circuit you used for your amp.
Thanks.
Alex |
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| Tubes4e4 |
For those designs shown using 3E29 / 829B / QQE04-60 / YL1060 strapped as triode in this thread, some of them use real strange operation points. Hence I would suggest to double check with the traced curves, which are available here:
3E29/829B/QQE04-60/YL1060 strapped as triode
Regards,
Tom Schlangen |
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| ilimzn |
| quote: | Originally posted by Tubes4e4
For those designs shown using 3E29 / 829B / QQE04-60 / YL1060 strapped as triode in this thread, some of them use real strange operation points. Hence I would suggest to double check with the traced curves, which are available here:
3E29/829B/QQE04-60/YL1060 strapped as triode
Regards,
Tom Schlangen |
Tom,
I wonder if you ever saw a dissipation disparity problem when tracing the curves - wildly different currents in the two sections, resulting in overheating of one section? i seem to remember reading something about it here a long while ago.
Also, i will take this oportunity to thank you for the traced curves for EL509 with low Vg2 and G2 driven. Would you happen to have real traced triode curves as well? I am also looking forward to finding triode curves for the EL/PL508 - perhaps wishful tinking, but you seem to be the person to ask when triode curves are needed :) |
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| alexg |
| quote: | Originally posted by AcidEye
Alex,
A proven design using the 832 can be found on:
http://www.audiohobbyist.com/projects/832.htm
I am still waiting for the output transformer to arrive, this 832 amplifier is on top of my project list :-) |
I saw that circuit, I might do that then. Thanks.
Has anybody used the 829/832 for SE?
Thanks |
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| wa4swj |
Hi Fellows,
Picture of my 832 amp is below. I used the Audio Hobbyist design and it works quite well. I have not hooked it up to my distortion analyzer yet but it sounds exceptionally good. Very open and plenty of punch. I used some slip on connectors from a terminal block for the plate connections - from a Phoenix terminal block.
Regards,
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| arnoldc |
Shouldn't you put some insulation on those horns? :eek: :eek: :eek:
Alex, the first few posts, including that one from Pete Milette has the 829 wired in triode, I think that's PSE. |
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| wa4swj |
Hi Arnold,
Well, I guess most people would insulate them. But I have no kids, no pets, no spouse and my girlfriend knows better than to touch those leads, so it's probably OK. It works for me but it might not work for everyone. Safety first and it is important.
The amp sounds great and I'm quite happy with it. The 832's work quite well. The plates glow just slightly red, which is how I like it. I did not put blue LED's in the bottom. And those are Hammond 1608 OPT's.
Regards, |
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| Audio_idiot |
Hi,
I design and build a low power Simple 832 pp not too long ago, sound bright, open, punchy and its nothing close to sweet to me.
Just watch out for the Screen Grid current. And since the cathode for the 2 beam tetrode are common, I have no idea as of how to balance the 2 plate currents.
Cheers |
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| alexg |
| quote: | Originally posted by arnoldc
Shouldn't you put some insulation on those horns? :eek: :eek: :eek:
Alex, the first few posts, including that one from Pete Milette has the 829 wired in triode, I think that's PSE. |
Thanks.
I will go with the PP configuration as per audiohobbyist.com, but might go for a better PSU design that I have learned from my mentors. |
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| Audio_idiot |
Hi Arnold,
Actually, the output stage is very tolorent to PS noise, I fine it sufficiently quiet from my 96db speakers with a single 330uf cap for the power stage, but more attention is required for the driver stage, and sounded lifely too. (And cheap too cool: )
I personally hear that it kills the sound if you regulate the voltage here. or pile up too much capacitors. But if your findings proove othterwise, please share your technique.:
I didn't do any measurements, but from the datasheet, it shows that this tube is highly distorted... BUT, to me, it distorted in a ear pleasing way ;)
Happy building |
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| Tubes4e4 |
Hi ilimzn,
| quote: | | Would you happen to have real traced triode curves as well? I am also looking forward to finding triode curves for the EL/PL508 - perhaps wishful tinking, but you seem to be the person to ask when triode curves are needed :) |
Triode strapped EL509 curves are on top of the tracing list, indeed. Probably not this weekend, though.
Regards,
Tom |
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| adalin |
| Im allmost finnished with my experimental 832 amp, here is a sneakpeak :) |
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| ilimzn |
| quote: | Originally posted by Tubes4e4
Hi ilimzn,
Triode strapped EL509 curves are on top of the tracing list, indeed. Probably not this weekend, though.
Regards,
Tom |
No hurry, as long as we all get to see them in some forseeable future :)
BTW just to be clear, my interest in EL509/519 trioded curves notwithstanding, when I wrote above about the EL/PL508, it was not a mistype. EL/PL509 liiks like a shorter EL/PL504 without the top cap, was used for vertical deflection in large screen color TVs, and has a 12W nominal plate dissipation, even though the structure inside is quite huge (about the same as a PL36 or PL500). |
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| alexg |
| quote: | Originally posted by adalin
Im allmost finnished with my experimental 832 amp, here is a sneakpeak :) |
That looks cool and far out! |
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| Wavebourn |
Holly-Molly! :D
Very impressive design. Also, you may not afraid microphonics'! :smash: |
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| soundbrigade |
Well, 829/832 classifies as UFO-tubes and this is what?? :hot:
UFU-tubes meets slimy monster from the Lousiana swamps:D
I have always wanted to do something crazy like this.:clown: |
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| adalin |
well, this is more an experiment with materials rather than with the sound ;)
It probably wont be a killeramp sonically, But I like to experiment with different ideas and designs |
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| soundbrigade |
Adalin, you're from Gothenburg??? You must take it to the DIY-summit on 21/4. You've heard about that?!
Else check HiFi-forum
What is the chassis made of? It looks either as molten bakelite or clay or an old motorblock for a BMC Cooper .......:) |
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| 7N7 |
I like these double beam tetrodes too. I have made curves for the ones Tom listed (should be QQVO6-40 Tom!)and also for QQVO7-50 and YL1071 (the best of the lot).
Copies with pleasure on request.
7N7 |
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| lumeimei |
| Picture of my FU 32(chinese) 832A |
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| alexg |
| quote: | Originally posted by lumeimei
Picture of my FU 32(chinese) 832A |
Can you share the schematic? Thanks. |
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| alexg |
| quote: | Originally posted by Audio_idiot
Hi,
I design and build a low power Simple 832 pp not too long ago, sound bright, open, punchy and its nothing close to sweet to me.
Just watch out for the Screen Grid current. And since the cathode for the 2 beam tetrode are common, I have no idea as of how to balance the 2 plate currents.
Cheers |
Finally built my 932 PP amp, very similar to what you have posted, but I got the idea of the phase inverter (self inversion) from diyparadise.com on Yeo's Simple EL84 circuit.
I initially breadboarded the amp using a center tapped choke for phase inversion, then I tried Yeo's circuit, both sounds good, but I like Yeo's circuit, it has less parts.
First I tried using 6n1p for driver, too much gain, used 12au7, same thing. Now I am using 6j5 and it sounds good!
I just got a pair of 12b4 which I will try to use for the driver.
I can't believe the bass out of this tubes.
If I did not build monoblocks, you can build a three tube push pull, and you can tell everybody it is SE.
:D |
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